Melamine-assisted pyrolytic synthesis of bifunctional cobalt-based core-shell electrocatalysts for rechargeable zinc-air batteries

Designing a highly activeand stable non-noble metal bifunctional oxygen catalyst for rechargeable Znair battery remains a great challenge. Herein, we develop a facile and melamine-assisted-pyrolysis (MAP) strategy for the synthesis of core-shell Co-based electrocatalysts@N-doped carbon nanotubes (Co@CNTs) derived from metal-organic frameworks. The Co@CNTs exhibited excellent bifunctional electrocatalytic performance for both oxygen evolution and reduction. DFT calculations demonstrated that the Gibbs free energy of the rate-determining step was small enough to improve ORR activities. As a result, a Zn-air battery assembled with Co@CNTs proves a lager power density, low voltage gap between charge-discharge and excellent stability. Thus, this work offers a facile strategy to realize the synthesis of non-noble metal electrocatalyst for Zn-air battery materials with high electrochemical performance. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

This study presents a facile synthesis method for cobalt-based nanotubes as non-noble metal catalysts for zinc-air batteries, demonstrating excellent bifunctional electrocatalytic performance and enhanced stability and power density in the battery system.